The present invention generally relates to the field of sealing members that are used in industrial fluid flow control applications and, more particularly, the present invention is concerned with an improved method of, and an apparatus for, enhancing the sealing capabilities of sealing members which are to be subjected to predetermined differential pressures on the opposite sides thereof during their normal use in a particular fluid flow control application.
Sealing members in general and, in particular O-ring sealing members, have been known and used in a wide variety of industrial applications for many years. For example, most of the industrial hydraulic control applications, as well as the majority of the pneumatic control applications, use O-rings as a primary sealing means. In addition, a large percentage of these industrial fluid pressure control applications involve the use of a spool valve. This is known to be particularly the case involving a pneumatic control system. Consequently, the leakage of O-ring sealing members that occurs around a spool valve is, and has continued to be, a problem of major concern to the industrial user. It has been felt that the leakage problem was primarily the result of an excessive amount of wear on the O-ring sealing member. It is known that one of the primary causes of such wear on O-ring sealing members is the result of abrasion. One of the major causes of such abrasion occurs when the O-ring sealing member passes the sharp edges of fluid passageways that are drilled in a spool bushing of a spool valve. The leakage of fluid passed an O-ring sealing member may be caused by phenomenon unrelated to the amount of wear that may have occurred to the O-ring sealing member.